Activation of MMP-9 by human lung epithelial cells in response to the cystic fibrosis-associated pathogen Burkholderia cenocepacia reduced wound healing in vitro

Abstract

Burkholderia cepacia complex is a group of bacterial pathogens that cause opportunistic infections in cystic fibrosis (CF). The most virulent of these is Burkholderia cenocepacia . Matrix metalloproteinases (MMPs) are upregulated in CF patients. The aim of this work was to examine the role of MMPs in the pathogenesis of B. cepacia complex, which has not been explored to date. Real-time PCR analysis showed that B. cenocepacia infection upregulated MMP-2 and MMP-9 genes in the CF lung cell line CFBE41o− within 1 h, whereas MMP-2, -7, and -9 genes were upregulated in the non-CF lung cell line 16HBE14o−. Conditioned media from both cell lines showed increased MMP-9 activation following B. cenocepacia infection. Conditioned media from B. cenocepacia -infected cells significantly reduced the rate of wound healing in confluent lung epithelia ( P < 0.05), in contrast to conditioned media from Pseudomonas aeruginosa -infected cells, which showed predominant MMP-2 activation. Treatment of control conditioned media from both cell lines with the MMP activator 4-aminophenylmercuric acetate (APMA) also resulted in clear activation of MMP-9 and to a much lesser extent MMP-2. APMA treatment of control media also delayed the repair of wound healing in confluent epithelial cells. Furthermore, specific inhibition of MMP-9 in medium from cells exposed to B. cenocepacia completely reversed the delay in wound repair. These data suggest that MMP-9 plays a role in the reduced epithelial repair observed in response to B. cenocepacia infection and that its activation following B. cenocepacia infection contributes to the pathogenesis of this virulent pathogen.

ADAM17 Mediates MMP9 Expression in Lung Epithelial Cells

“…MMP9 is not produced by resident cells in the normal lung; however, in response to various forms of stimulation, MMP9 is expressed, produced, and secreted by many inflammatory cells and some airway structural cells [22], [23]. LPS, or endotoxin, is a predominant, integral structural component of the outer membrane of gram-negative bacteria and one of the most potent microbial initiators of inflammation [24].…”

Porphyromonas gingivalispromotes invasion of oral squamous cell carcinoma through induction of proMMP9 and its activation

“…Among the MMP family members, MMP2 and MMP9 have been shown to be strongly involved in carcinoma cell invasion, which is an essential factor for cancer progression and metastasis (Krüger et al, 2005). MMP9 is reportedly activated by Burkholderia cenocepacia, Brucella abortus, H. pylori, Salmonella enterica, and Streptococcus pyogenes bacterial infection in gastric carcinoma cells, monocytes, lung epithelial cells, and synoviocytes (Tamura et al, 2004;Oliveira et al, 2006;Ramu et al, 2008;Scian et al, 2011;Wright et al, 2011), and migration and invasion of infected cells were accelerated. Also, cellular production of proMMP9 was shown to be induced in vitro by P. gingivalis as well as by stimulation with its lipopolysaccharide (LPS) (Andrian et al, 2007;Jotwani et al, 2010).…”

Impaired Airway Epithelial Barrier Integrity in Response to Stenotrophomonas maltophilia Proteases, Novel Insights Using Cystic Fibrosis Bronchial Epithelial Cell Secretomics

“…We identified MMP2 (matrix metalloproteinase-2), a type IV collagenase as a candidate disease protein in the up-regulated protein network. P. aeruginosa has been shown to increase MMP-2 activity in CFBE41o-cells and a gain of functional MMP-2 and loss of function of TIMPs 1 and 2 are possible causes of epithelial damage in S. maltophilia lung disease (23). Other important anti-proteases which were downregulated included alpha-1 antitrypsin and plasminogen activator inhibitor (PAI-1), an inhibitor of fibrinolysis, the absence of which predisposes the individual to a haemorrhagic diathesis.…”

“…There are many example reports using bacterial CS to study the behavior of virulence factors in vitro (3,(21)(22)(23). As a first step toward assessing the role, if any, of secreted proteases in the pathogenesis of S. maltophilia pulmonary infection, we examined the effect of differing concentrations of K279a CS (5 and 10% v/v) on CFBE41o-cell monolayers compared with untreated control cells ( Figure 1A).…”